For thousands of foster children, the search for a permanent family is framed by a display in the “heart gallery,” an annual showcase where heartwarming pictures of smiling, laughing and frolicking children beckon to prospective parents.

But A.B., a 16-year-old foster child from Jacksonville, was being sold with an entirely different set of photos. She wore high heels, a black skirt and a tight tank top that showed off her cleavage.

The caption for A.B.’s picture: “Experience me to know I will be your best!”

An ad in Backpage.com gushed that the girl’s “hands will be your best asset,” and added “$100 gift donation due upon arrival.”

The Backpage photos were a tawdry milestone in A.B.’s descent into prostitution — documented as part of the federal prosecution of her alleged pimp, Gregory Goellet Hodge Jr., who, authorities say, recruited the girl near the foster-care group home where she lived.

The case, which is still pending, shares eerie similarities to the arrest last week of four Miami-Dade men who, police say, recruited foster children from a group home to work at a Homestead brothel.

The girls caught up in the Miami prostitution ring share the same foster-care agency as A.B.: the Children’s Home Society of Florida.

Although the trafficking in underage girls into prostitution is not limited to kids in foster care, children’s advocates say such children are particularly attractive targets to pimps: They are separated from family, often poorly supervised, crave attention and affection, and often run away from caregivers to the streets.

“You would have to be naive to think that pimps do not realize this,” said Staca Shehan, director of case analysis for the National Center for Missing and Exploited Children in Virginia. “This class of minors are vulnerable. It’s not uncommon for foster children to run away. Once you run away, how do you support yourself? What do you do to find shelter and safety? What do you do to provide that for yourself?’’

The investigation into the underage prostitution of foster children in Miami continues.

State Attorney Katherine Fernández Rundle said last week that her agency, together with police, intended to file additional charges in cases where men have lured young girls into the sex trade, and will vigorously pursue the girls’ clients.

Sources told The Miami Herald last week that judges at Miami-Dade’s Children’s Courthouse who preside over child-welfare cases were given lists of girls in their divisions who police believe had been trafficking victims. The lists named several teenagers in addition to the four identified by their initials in last week’s arrests.

Sources also told the newspaper that such trafficking was not limited to foster-care group homes operated by Children’s Home Society.

“These girls all had very tragic, complicated pasts,” said David Wilkins, secretary of the Department of Children & Families, which pays the group-home bills for foster children. “All these girls have seen the hard side of life.”

When asked what he would say to people concerned about two such cases in less than 12 months at CHS facilities, President/CEO David Bundy said he would point to the company’s years of experience and emphasize the troubled backgrounds of the teens they receive.

“It’s a population of kids who, unfortunately, have been mistreated, do not have any good adult role models, and set up with bad actors who show them affection and convince them that they care about them, in some cases, and really take advantage of them,” Bundy said.

In Jacksonville, a plea agreement filed in the Middle District of Florida outlined the accusations against Hodge and how he allegedly shopped around A.B. As part of the deal, Hodge would have pleaded to one count of sex trafficking a minor, which carried a minimum of 10 years in prison, the records said. Other counts would have been dropped.

But the deal didn’t become final, and the case is ongoing. Hodge’s lawyer declined to comment.

Here is how the agreement described the business and A.B.’s role:

A.B. was part of Hodge’s massage business. His plan was simple: Recruit women willing to work for him, put advertisements out for massages and body rubs under the category of “Jacksonville Adult Entertainment,” and split the money between him and the girls.

“Yeah,” she replied, telling him she was 17, padding her real age by a year. She hoped he thought she was 18.

Hodge soon recruited her for his business.

Wilkins told The Miami Herald that the teen eventually became more than just an employee. Before A.B. left the group home, “she recruited a lot of the other girls in the home,” he said.

Like a teenager in the Miami case, identified as S.S., A.B. sought out other girls to share her plight — a development that is not uncommon in human trafficking, Shehan said. “Once they’ve recruited a victim into their confidence, they will send her back into the foster-care system to recruit other victims,” she said.

A.B. was with the Children’s Home Society because of her involvement with the juvenile justice system. But soon after meeting Hodge, she was staying in his home, instead, the plea documents said. She was there about a month.

Her first advertisement went up July 14 on Backpage.com. He called her “Daisy” and lured in potential clients with the promise of a “private massage specialist.”

The ad boasted about her willingness to travel, her professional session experience and how her hands were her best asset.

The pictures attached showed off her other assets. One showed the front of her body, one showed the side of her body, and the third showed her cleavage, the court records said. She wore heels, a short skirt and a tight tank top. They showed the many curves of her body, but all stopped before her chin. They never showed her face.

Her first job was a commercial sex act.

“I thought it was supposed to be a massage,” A.B. recalled telling Hodge.

He replied, “Well, do whatever you have to do for the money.”

The ad went up on Backpage.com, which has gotten scrutiny from across the country for hosting ads that, like with A.B., are veiled sales of girls for sex. It’s owned by Village Voice Media Holdings LLC. Critics say the ads make business even easier for the pimps.

Liz McDougall, general counsel for Village Voice Media, said the company screens ads in its adult section twice before they go up, once by a computer and once by a person, and a third time after the ads are published looking for signs of illegal activity. Once they’ve been notified of a law enforcement investigation, they immediately cooperate, she said.

But they don’t think removing the ads solves the problem, McDougall said. They believe the ads would only move to another company, one that might be less inclined to work with police or not required to because it’s based overseas.

Critics say they don’t believe Backpage.com does enough and remains a clearinghouse for trafficking.

In Jacksonville, A.B.’s ad was renewed five times in less than a month. The ad had a phone number, court records said, which rang the phone of a woman who worked for Hodge.

Like the other women, A.B. collected money from clients and gave it to Hodge, who handed her a cut. She told investigators she had about three clients a day. The girl only remembered some of her customers. Investigators tracked down one, living in a luxury condominium on the St. John’s River in downtown Jacksonville called The Strand. Twice, she told agents, Hodge drove her there; she went to the customer’s unit and had sex with him for money.

She got $140 each time, which she split with Hodge.

Afterward, she would call Hodge to pick her up.

Detectives later interviewed the client, who was not indicted, according to the plea agreement. They asked if he and “Daisy” had sex.

“It depends on your definition of sex,” he told them, according to the documents.

The business eventually unraveled when Hodge decided to stiff his employee, sources told the newspaper.

A.B. left Hodge and found another pimp. Together with the new pimp, sources said, A.B. abducted Hodge and a young relative, tied him up and ransacked his house looking for money. The incident led to her arrest, and the discovery of Hodge’s business.

In the end, A.B. retained some honor, sources said. She took from Hodge only the money she said he owed her.